I'm an atheist and I do not fear death.
This is distinct from living and avoiding death. I'd be terrified to be in a World War One trench, bayonets fixed, waiting for the whistle to go over the top. But as far as dying after a long life in my old age; no. Don't get me wrong, I'd prefer to live for a thousand years in health, but when a natural death comes I don't fear returning to the state I was in before birth.
When death inevitable approaches me, I will console myself that I will live on in the flesh of my children and the memories of my loved ones.
I thought Richard Dawkins made a very eloquent quote about this;
“We are going to die, and that makes us the lucky ones. Most people are never going to die because they are never going to be born. The potential people who could have been here in my place but who will in fact never see the light of day outnumber the sand grains of Arabia. Certainly those unborn ghosts include greater poets than Keats, scientists greater than Newton. We know this because the set of possible people allowed by our DNA so massively exceeds the set of actual people. In the teeth of these stupefying odds it is you and I, in our ordinariness, that are here.We privileged few, who won the lottery of birth against all odds, how dare we whine at our inevitable return to that prior state from which the vast majority have never stirred?”